As organic materials which are included in optical devices such as OLED, LCD, etc. are very vulnerable to oxygen in the air or water vapors, their power reduction or early performances degradation may occur when exposed to oxygen or water vapors. Therefore, methods for extending the lifespan of the devices have been developed by protecting them using a metal or glass, but the metal is generally lack of transparency and the glass is short of flexibility.
Therefore, clear barrier films or encapsulating compositions having flexibility to be used for encapsulating optical devices including a light, bendable, and flexible OLED have been developed and in particular, silicon-based polymeric compounds having excellent light resistance and light transparency have been continuously preferred and developed as an encapsulating material for optical devices.
As a result of this, a composition of which the physical properties are improved by using silsesquioxane has been disclosed, but since the silsesquioxane used in there is a powder-type having a mixed structure of a ladder and cage, it is inappropriate as an encapsulating material for most optical devices, especially, LED which require a solvent-free process.
Further, a composition of which the adhesive strengths and barrier properties are enhanced by using silazane has been disclosed, but when applied to a thick film (1 mm or over) instead of a thin film, it caused a severe outgassing problem, making it difficult to achieve even film properties and its barrier properties were thus degraded.